Vega Launch Vehicle

_Vega is the lightweight
workhorse of Arianespace and the European Space Agency that made its maiden voyage
in 2012 after 13 years of development and testing.

The Vehicle was built to
haul small payloads into a variety of orbits including Low Earth, Sun Synchronous
and Polar Orbits. Vega is launched from Kourou, French Guiana being operated by Arianespace. Along with the heavy-lift Ariane 5 and the medium-lift Soyuz
2-1, Vega completes Arianespace’s broad range of Launch Vehicles operating
from French Guiana. Vega offers customers a cost-effiicient opportunity to
orbit smaller payloads.

Vega is a three-stage all-solid launch vehicle with an optional liquid fueled upper stage for re-start and precise injection capability. The launch vehicle stands 29.9 meters tall, has a main diameter of 3.03 meters and a liftoff mass of 137,000 Kilograms. The Rocket can lift up to 2,500 Kilograms of Payloads –
depending on the target orbit.

Image: ESA

Photo: ESA/Arianespace/CNES

Vega Specifications

Type

Vega

Height

29.9m

Diameter

3.025m

Launch Mass

137,000kg

Stages

4

Stage 1

P80 FW

Stage 2

Z23 FW

Stage 3

Z9 FW

Stage 4

AVUM

Mass to LEO

1,500kg (700km Polar Orbit)

Payload Capability

300 to 2,500kg

Launch Cost

~$23 Million

First Stage

Type

P80 FW

Inert
Mass

7,431kg

Diameter

3m

Length

11.2m

Propellant

HTPB 1912 Solid

Propellant
Mass

88,365kg

Guidance

From AVUM

Propulsion

P80FW (SRM)

Thrust
at Sea Level

2,261kN

Impulse

280s

Max.
Pressure

95bar

Burn
Time

106.8sec

Attitude
Control

Gimbaled 6.5°
Nozzle

Stage
Separation

Cutting
Charge&Retro Thrusters

S1 Design

Credit: Arianespace - Vega Payload Planner's Guide

Second Stage

Type

Z23 FW

Diameter

1.9m

Length

8.39m

Inert Mass

1,845kg

Propellant

HTPB 1912 Solid

Propellant
Mass

23,906kg

Guidance

From AVUM

Propulsion

ZEFIRO 23 SRM

Thrust

1,196kN

Impulse

289s

Burn Time

71.7sec

Max.
Pressure

95bar

Attitude
control

Gimbaled 7° Nozzle
with electro

Actuator

Stage
Separation

Cutting
Charge&Retro Thrusters

Third Stage

Type

Z9 FW

Diameter

1.9m

Length

4.12m

Inert
Mass

833kg

Propellant

HTPB 1912 Solid

Propellant
Mass

10,115kg

Guidance

From AVUM

Propulsion

ZEFIRO 9 SRM

Thrust

225kN

Impulse

295s

Burn Time

109.6sec

Max.
Pressure

95bar

Attitude
control

Gimbaled 6°
Nozzle with electro

Actuator

Stage
Separation

Clamp Band &
Springs

Fourth Stage

Type

AVUM

Diameter

2.18m

Length

2.04m

Inert
Mass

418kg

Propellant

Hydrazine/Nitrogen
Tetroxide

Propellant
Mass

550kg

Propulsion

RD-869

Thrust

2.45kN

Impulse

315.5s

Burn Time

Up to 667sec

Engine
Start

Up to 5 Restarts

Attitude
control

Gimbaled 9° Nozzle

2x3 50-N Nitrogen
Thrusters

Propellant

26kg

Avionics

Inertial 3-axis
Platform

Engine
Start

On-Board Computer

Attitude
control

TM&RF Systems

AVUM Design

Credit: Arianespace - Vega Payload Planner's Guide

Payload Fairing

Diameter

2.6m

Length

7.88m

Mass

490kg

Separation

Vertical:
Pyrotechnic Tubes

Horizontal: Clamp
Band

Construction

Sandwich
Construction

CFRP Sheets

Aluminum
Honeycomb Core

Acoustic
Protection

Fabric covered
Foam Sheets

Payload Adapter

Type

Clampband

Diameter

0.937m

Mass

60kg

Photo: ESA - J. Huart

Vehicle Description

Photo: ESA - J. Huart

First Stage

_The Core first Stage of the Vega
Vehicle has on overall length of 11.5 meters without nozzle. It is 3 meters in
diameter. The Motor is based on a high-performance European Solid Rocket Motor.
P80 FW SRM has a carbon-epoxy filament wound
monolithic motor case that is protected by a low density thermal insulation.
The stage uses HTPB 1912 Solid Propellant. This type of propellant has a finocyl type
grain shape and is based on flight-proven propellants that have been modified.

The nozzle contains a 3-D Carbon-Carbon Throat and a protected flexible
joint allowing the nozzle to be moved for vehicle control. The carbon-phenolic
exit cone has an actuator attachment ring which is joined to
the exit cone by overlapped structures. First Stage Thrust Vector Control is
accomplished by two electro actuators moving the nozzle. Vega’s
Electro-actuators Piloting Equipment (EPEV) controls pitch and yaw during first
stage ascent.

Inside the rear bay are Launch Pad interfaces used to hold the
vehicle in place. Also inside the rear bay are the first stage Thrust Vector
Control actuators and batteries. Engine Ignition is accomplished with a
ignition pyro circuit. The 1T2 inter-stage provides the structural connection
of the two stages. Inside the adapter are Range Safety Systems with batteries
and a remote unit with destructive pyrotechnics. Stage Separation is
accomplished with linear cutting charges and 6 retro rockets with ignition
circuits to separate the two stages.

Second Stage

_The
second stage is also a solid-fueled rocket stage using a ZEFIRO 23 Solid Rocket
Motor. The stage is 8.5 meters long and 1.9 meters in diameter and also uses
HTPB Propellant. Stage and Nozzle design are similar to the P80 FW. Nozzle
deflection is 7 degrees into every direction however. On the second stage side
of the 1T2 interface is the 2nd stage Thrust Vector Control
Equipment (two electro actuators mated to the nozzle and Li-Ion batteries).
Second stage ignition is achieved by a pyro-circuit that is also part of 1T2.
2T3 forms the link between second and third stage and has a aluminum shell with
stiffeners on the inner side. Of importance for the second stage, 2T3 contains
a stage Safety system and
associated subsystems.

S2 Design

Credit: Arianespace - Vega Payload Planner's Guide

Third Stage

_Z9 is
the third stage of the vehicle. It is 3.5 meters in length and 1.9 meters in
diameter and is based on the second and first stage design. The nozzle of the
ZEFIRO 9 can be moved 6 degrees in every direction. The 2T3 interface contains
TVC components, ignition pyros and the third stage Thrust Vector Control Box
including a Digital Control Module and Power Drive Unit. Inside the 3TAVUM
interstage section, most of the vehicle’s avionics are located that provide
vehicle guidance for the first three stages of Vega. 3TA is 0.82m in length and
is made of a a
cylindrical aluminum shell structure. Stage Separation is accomplished by a
clamp-band and springs pushing the stages apart.

S3 Design

Credit: Arianespace - Vega Payload Planner's Guide

AVUM

_The Attitude and Vernier Upper Module (AVUM) is the 4th multifunctional stage of the Vega Launch Vehicle. It controls the first three stages via its avionics units and onboard computers and it makes the final engine burns finalizing the vehicle’s trajectory.

AVUM is comprised of two parts. The APM – AVUM Propulsion Module – houses the 4th stage propulsion system and the attitude control system. The main engine and four spherical fuel tanks are mounted on a horizontal platform along with a external cylindrical skirt and Attitude Control System Engines. A RD869 single chamber engine provides a multiple restart capability. It is certified to re-ignite up to five times. It burns liquid propellants (Nitrogen Tetroxide and Hydrazine) supplied by a regulated pressure system. The propellants are stored in four titanium tanks each holding up to 142 liters. Tank pressurization is maintained by gaseous Helium which is stored in a single vessel. Operational tank pressure is 35.6 bars.

Attitude Control is provided by moving the main engine or by using the attitude control system while the vehicle is coasting. The ACS uses two clusters of three cold gas thrusters providing 50 Newtons of thrust each and being fed with Nitrogen from one central tank. During powered flight of Z9 and AVUM, the system is used for roll-control and spin-up only.

The AVUM Avionics Module (AAM) houses almost all of the avionics installed on the Vega Launcher. Inside AAM are the flight control systems, telemetry units, the power supply, thermal control systems and the safety system. These avionics enable Vega to conduct its mission autonomously and execute all mission operations except range safety which has to be manually activated. The AVUM Control System provides attitude control and stabilization, navigation and guidance as well as vehicle management and commanding during the entire flight of the vehicle. Navigation and Attitude data is provided by an Inertial Measurement Unit. The Onboard Computer executes all guidance related tasks and forms the core of Vega’s brain.

Photo: ESA

Payload Fairing

The Payload Fairing is positioned on top of the stacked vehicle and its integrated payloads. It protects satellites or other spacecraft against aerodynamic, thermal and acoustic environments that the vehicle experiences during atmospheric flight. When the launcher has left the atmosphere, the fairing is jettisoned by pyrotechnically initiated systems. One system splits the fairing vertically, the other frees the to halves. The fairing then falls back to Earth and burns up in the atmosphere. Separating the fairing as early as possible increases ascent performance. Vega's fairing is cylindrical in shape, and has an inner diameter of 2.6m.

Payload Adapters

Payload Adapters interface with the vehicle and the payload and are the only attachment point of the payload on the Launcher. They house equipment that is needed for Spacecraft Separation and ensure that the satellite or spacecraft is secured during powered flight. A variety of payload adapters will be available to satellite customers in order to fit a large number of spacecraft dimensions and interfaces, however, for Vega there is currently only one off-the-shelf device that would not require lengthy redesigns.

Please consider supporting this website by making a small donation. Our reader's support keeps the site open & improving.